Cannula



FIG. 1 is a perspective view of a cannula, showing our new design;

FIG. 2 is a top plan view thereof, the bottom plan view being identical;

FIG. 3 is an end elevational view thereof;

FIG. 4 is a side elevational view thereof, the opposite side beingidentical; and

FIG. 5 is an end elevational view thereof, opposite that shown in FIG.3.

The ornamental design for a cannula, as shown and described.